cpuidle: calxeda: Add missing __iomem annotation

Added missing __iomem annotation in order to fix the following
sparse warnings:

drivers/cpuidle/cpuidle-calxeda.c:44:24: warning: incorrect type in argument 1 (different address spaces)
drivers/cpuidle/cpuidle-calxeda.c:44:24:    expected void [noderef] <asn:2>*<noident>
drivers/cpuidle/cpuidle-calxeda.c:44:24:    got void *extern [addressable] [toplevel] scu_base_addr
drivers/cpuidle/cpuidle-calxeda.c:56:24: warning: incorrect type in argument 1 (different address spaces)
drivers/cpuidle/cpuidle-calxeda.c:56:24:    expected void [noderef] <asn:2>*<noident>
drivers/cpuidle/cpuidle-calxeda.c:56:24:    got void *extern [addressable] [toplevel] scu_base_addr

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

drivers/cpuidle/cpuidle-calxeda.c

@@ -35,7 +35,7 @@
 #include <asm/cp15.h>
 
 extern void highbank_set_cpu_jump(int cpu, void *jump_addr);
-extern void *scu_base_addr;
+extern void __iomem *scu_base_addr;
 
 static noinline void calxeda_idle_restore(void)
 {